Archery cushion plunger

ABSTRACT

The present disclosure relates to an archery cushion plunger in which a structure is changed so that a plunger shaft in contact with an arrow shaft passes through a center of an elastic member, the plunger shaft stably grips the center of the elastic member, and thus deformation of the elastic member may be fundamentally prevented even when a pressure is applied to front and rear sides of the elastic member during adjustment of a tensile force. Therefore, a tip portion of the plunger in contact with the arrow shaft is always in horizontal contact with the arrow shaft to stably compensate for horizontal vibration, stable flight of an arrow is induced, and thus a hit rate of the arrow can be improved.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2022-0096982 filed on Aug. 3, 2022, the disclosure ofwhich is incorporated herein by reference in its entirety.

BACKGROUND 1. Field of the Invention

The present disclosure relates to an archery cushion plunger, and moreparticularly, to a cushion plunger that adjusts a strength of a pressurepoint, compensates for horizontal vibrations that occur in an arrowshaft when an arrow is fired from a bowstring and is accelerated, andthus induces right flight of the arrow.

2. Discussion of Related Art

In general, in archery that is a Western-style bow, a stabilizer, acushion plunger, or the like are used as an auxiliary device that helpsan arrow fired from a bowstring of a body that shoots the arrow byhanging the arrow on the bowstring to fly correctly in addition to thebody.

Among them, the cushion plunger, which is a device that adjusts astrength of a pressure point, compensates for a horizontal vibrationthat occurs in an arrow shaft when an arrow is fired from a bowstringand is accelerated, minimizes a paradox phenomenon in which the arrowthat leaves the bowstring flies while shaking in a left-right directionlike a fish, and thus serves to help the arrow fly correctly.

Various examples of this cushion plunger have been proposed in a numberof related documents including Korean Patent Publication No.10-2017-0121592, Korean Patent Publication No. 10-2016-0063828, U.S.Pat. Nos. 4,697,323, 5,081,980, 5,359,984, and 5,375,584, JapaneseUtility Model Registration No. 20-3175621, and the like.

The cushion plunger according to the relate art including the relateddocuments compensates for the horizontal vibration of the arrow shaft byadjusting a tensile force and pressure of a spring provided inside thebody through a screw. That is, by adjusting the tensile force of theplunger by rotating the screw in a tightening direction with respect toa housing to increase the tensile force of the spring or rotating thescrew in an untightening direction to decrease the tensile force of thespring, the arrow leaving the arrow shaft can fly stably.

FIG. 1 is a schematic cross-sectional view illustrating an example of acushion plunger according to the related art.

Referring to FIG. 1 , the cushion plunger 10 according to the relatedart includes a sleeve 11, a plunger 12 embedded in the sleeve 11 andhaving a tip portion 12 a that protrudes and retracts to buffer alateral pressure of an arrow shaft 1 (see FIG. 2 ), a spring 13 that isembedded in the sleeve 11 and applies a pressure to the plunger 12, atensile force adjustment bar 14 that adjusts a tensile force of thespring 13, and a tensile force adjustment housing 15 that adjusts thetensile force of the spring 13 by linearly moving the tensile forceadjustment bar 14.

Operating characteristics of the cushion plunger 10 having thisstructure according to the related art will be described.

When the tensile force adjustment housing 15 rotates about the sleeve11, the tensile force adjustment bar 14 moves along the sleeve 11 inconjunction with the rotation. In this process, the tensile force of thespring 13 is adjusted to compensate for a horizontal vibration of thearrow shaft so that an arrow can fly stably.

However, the cushion plunger 10 according to the related art has thefollowing problems, which will be described in conjunction with FIG. 2 .FIG. 2A is a view illustrating a normal state, and FIGS. 2B and 2C areviews illustrating a state in which a spring is deformed in an up-downdirection with respect to a center line CL.

As illustrated in FIG. 2A, only when a tip portion of the plunger 12 isin horizontal contact with the virtual center line CL, the arrow shaft 1can stably fly, and a hit rate can be improved. However, in the cushionplunger 10 according to the related art, in a process of adjusting thetensile force, as illustrated in FIGS. 2B and 2C, the spring 13 istwisted to one side with respect to the center line CL due to a gap g(see a portion “A” of FIG. 1 ) present between the spring 13 and thesleeve 11 for connecting the tensile force adjustment bar 14 and theplunger 12. Accordingly, a lateral pressure applied to the arrow shaft 1is twisted, making stable shooting difficult and reducing a hit rate ofthe arrow.

RELATED ART DOCUMENT Patent Document

KR 10-2017-0121592 A, 2017 Nov. 2.

KR 10-2016-0063828 A, 2016 Jun. 7.

KR 10-2020-0113157 A, 2020 Oct. 6.

U.S. Pat. No. 5,375,584 B1, 1994 Dec. 27

SUMMARY OF THE INVENTION

Thus, the present disclosure proposes an objective for solving theabove-described problem of the related art.

The present disclosure is directed to providing an archery cushionplunger in which a tip portion of a plunger in contact with an arrowshaft is always in horizontal contact with the arrow shaft to stablycompensate for horizontal vibration, stable flight of an arrow isinduced, and thus a hit rate of the arrow can be improved.

Further, the present disclosure is not limited to the above-describedobjective, and in addition, various objectives may be additionallyprovided through technologies described through the followingembodiments and the appended claims.

An archery cushion plunger includes a sleeve, a plunger shaft thatbuffers a lateral pressure of an arrow shaft through a tip portionexposed to one end of the sleeve, an elastic member which is embedded inthe sleeve and has a front surface horizontally stopped and supported onthe plunger shaft in a direction of the arrow shaft and through whichthe plunger shaft is coupled at a center thereof, a tensile forceadjustment cylinder into which a rear part of the plunger shaft isslidably inserted and of which a front surface is in contact with a rearsurface of the elastic member so that the tensile force adjustmentcylinder is horizontally stopped and supported, and a tensile forceadjustment housing that is screw-coupled to an outer surface of thesleeve to rotate about the sleeve and adjusts a tensile force of theelastic member by linearly moving the tensile force adjustment cylinderalong the plunger shaft while linearly moving along the sleeve in arotational direction.

The archery cushion plunger may further include a ball plunger thatmoves into a hollow of the tensile force adjustment housing through afastening hole formed in the tensile force adjustment housing and isvertically coupled to a tensile force adjustment groove formed in a rearpart of the sleeve inserted into the tensile force adjustment housing.

An alignment key groove may be formed in the outer surface of the sleevein a horizontal cut surface structure such that the alignment key grooveis horizontally parallel to a first tensile force adjustment grooveamong the tensile force adjustment grooves formed in the sleeve.

The tensile force adjustment cylinder may include an outer ring, aninner ring inserted into the outer ring, and a ball installed betweenthe outer ring and the inner ring.

The plunger shaft may include a front part having the tip portion, arear part connected to a rear end of the front part and inserted intothe tensile force adjustment cylinder, and a step part that is formed ata boundary between the front part and the rear part, protrudes outersurfaces of the front part and the rear part, and is in contact with thefront surface of the elastic member to be stopped and supported.

A separation prevention step by which a step part of the plunger shaftsupported by the front surface of the elastic member in the direction ofthe arrow shaft is stopped may be formed inside the sleeve.

The archery cushion plunger may further include a fixing nutscrew-coupled to the outer surface of the sleeve.

When viewed in the direction of the arrow shaft, the tensile forceadjustment housing may be formed in a polygonal structure.

The front surface of the rear force of the elastic member may bepolished to have a surface step of 0.3 mm or less.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentdisclosure will become more apparent to those of ordinary skill in theart by describing exemplary embodiments thereof in detail with referenceto the accompanying drawings, in which:

FIG. 1 is a cross-sectional view illustrating an example of a cushionplunger according to the related art;

FIG. 2 is a view illustrating deformation of a spring of the cushionplunger having the structure of FIG. 1 ;

FIG. 3 is an assembly perspective view illustrating an archery cushionplunger according to an embodiment of the present disclosure;

FIG. 4 is an exploded perspective view of the archery cushion plungerillustrated in FIG. 3 ;

FIG. 5 is an assembly cross-sectional view of the archery cushionplunger illustrated in FIG. 3 ; and

FIG. 6 is a front view illustrating an elastic member illustrated inFIG. 4 .

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Advantages and features of the prevent disclosure and methods ofachieving the advantages and the features will become apparent withreference to embodiments which will be described below in detailtogether with the accompanying drawings. However, the present disclosureis not limited to embodiments disclosed below and may be implemented invarious different forms.

In the present specification, the present embodiment is provided tocomplete the disclosure of the present disclosure and to completelyinform the scope of the present disclosure to those skilled in the artto which the present disclosure pertains. Further, the presentdisclosure is merely defined by the scope of the appended claims. Thus,in some embodiments, well-known components, well-known operations, andwell-known technologies are not described in detail in order to avoid anambiguous interpretation of the present disclosure.

Further, throughout the specification, the same reference numerals referto the same components. Further, terms used (mentioned) in the presentspecification are intended to describe the embodiments and are notintended to limit the present disclosure. In the present specification,a singular form also includes a plural form unless specificallymentioned in a phrase. Further, components and operations mentioned as“include (or be provided with)” do not exclude the presence or additionof one or more other components and operations.

Unless otherwise defined, all the terms (including technical andscientific terms) used herein may be used as meanings that may becommonly understood by those skilled in the art to which the presentdisclosure pertains. Further, terms defined in commonly useddictionaries are not interpreted ideally or excessively unless the termsare defined.

Hereinafter, embodiments of the present disclosure will be described indetail using the accompanying drawings.

FIG. 3 is a schematic assembly perspective view for describing anarchery cushion plunger according to an embodiment of the presentdisclosure, FIG. 4 is an exploded perspective view, and FIG. 5 is anassembly cross-sectional view.

Referring to FIGS. 3 to 5 , an archery cushion plunger 20 according tothe embodiment of the present disclosure may be provided such that a tipportion 221 a of a plunger shaft 22 is not twisted about a virtualcenter line and is always in contact with an arrow shaft 1 in ahorizontal direction. Thus, a horizontal vibration of the arrow shaft 1is always stably compensated for, so that an arrow can fly stably.

As illustrated in FIG. 2A, in the archery cushion plunger 20 accordingto the embodiment of the present disclosure, two methods are proposed asa method in which the tip portion 221 a of the plunger shaft 22 isalways in horizontal contact with the arrow shaft 1. First, the plungershaft 22 is coupled to pass through an elastic member 23. Second,contact surfaces of both ends of the elastic member 23 that is in directcontact with the plunger shaft 22 and a tensile force adjustmentcylinder 24 are precisely polished, thereby improving surface flatness.

As illustrated in FIGS. 2B and 2C, in the related art having a structurein which a spring 13 connects a plunger 12 and a tensile forceadjustment bar 14, when a force is applied in a direction from thetensile force adjustment bar 14 to the plunger 12 to adjust a tensileforce due to characteristics of the spring 13, the spring 13 iscontracted, and in this process, is twisted away from the center lineCL.

In order to solve this problem, as illustrated in FIG. 5 , in thearchery cushion plunger 20 according to the embodiment of the presentdisclosure, a rear part 222 of the plunger shaft 22 passes through theelastic member 23 made of a compression spring (coil spring) and isinserted into and coupled to the tensile force adjustment cylinder 24.

In this structure in which the plunger shaft 22 is coupled through theelastic member 23, the plunger shaft 22 serves to grip deformation ofthe elastic member 23. That is, when a pressure is applied to theelastic member 23 between the plunger shaft 22 and the tensile forceadjustment cylinder 24 and thus the elastic member 23 is about to bedeformed by a pressing force, the plunger shaft 22 is centered so thatthe elastic member 23 is not deformed, and thus twisting deformation ofthe elastic member 23 is prevented.

In contrast, in the related art, as illustrated in FIG. 1 , since acentral axis is not present in the spring 13, when a pressure is appliedto the spring 13 between the plunger 12 and the tensile force adjustmentbar 14, twisting deformation may occur in a space formed due to a gap gby the pressing force applied to the spring 13. However, in theembodiments of the present disclosure, this deformation does not occur.

Meanwhile, in the present disclosure, in order to maintain the plungershaft 22 horizontal, a sleeve 21 and the tensile force adjustmentcylinder 24 are assembled and installed in a horizontally aligned state.That is, a front part 221 of the plunger shaft 22 is closely coupledthrough an inside of the sleeve 21, and the rear part 222 is closelyinserted into and coupled to an inside of the tensile force adjustmentcylinder 24. In this case, as the sleeve 21 and the tensile forceadjustment cylinder 24 are assembled and installed in a horizontallyaligned state, the plunger shaft 22 may be horizontally maintainedbetween the sleeve 21 and the tensile force adjustment cylinder 24.

FIG. 6 is a front view illustrating an elastic member illustrated inFIG. 4 .

As illustrated in FIGS. 5 and 6 , the elastic member 23 according to thepresent disclosure, which is a compression spring, is installed betweena step part 223 of the plunger shaft 22 and a front surface 24 a of thetensile force adjustment cylinder 24.

A front surface 23 a of the elastic member 23 is in close contact with arear surface of the step part 223 of the plunger shaft 22, and a rearsurface 23 b thereof is in close contact with the front surface 24 a ofthe tensile force adjustment cylinder 24. In this case, when the elasticmember 23 is pressed, the entire front surface 23 a may be in closecontact with the step part 223 of the plunger shaft 22, and the entirerear surface 23 b may be uniformly in close contact with the frontsurface 24 a of the tensile force adjustment cylinder 24.

To this end, in the elastic member 23, the front surface 23 a isprecisely polished so that the front surface 23 a is horizontally inclose contact with the step 223 of the shaft 22, and the rear surface 23b is also precisely polished so that the rear surface 23 b is nottwisted when in close contact with the front surface 24 a of the tensileforce adjustment cylinder 24.

The front surface 23 a and the rear surface 23 b of the elastic member23 may be polished so that a surface step therebetween is 0.3 mm orless, preferably 0.2 mm, and more preferably 0.1 mm.

As illustrated in FIG. 4 , the plunger shaft 22 according to theembodiment of the present disclosure can increase the degree of adhesionbetween the sleeve 21 and the elastic member 23 to prevent shakingduring a horizontal (left-right) linear reciprocating movement.

The plunger shaft 22 may be made of stainless steel that is resistant tocorrosion and oxidation. For example, the plunger shaft 22 includes afront part 221 and a rear part 222 formed of a round bar. Further, thestep part 223 formed in a circular ring shape protrudes from outersurfaces of the front part 221 and the rear part 222 at a boundarybetween the front part 221 and the rear part 222.

The front part 221 and the rear part 222 may be integrally formed as around bar. The step part 223 may be formed by fastening a separatelymanufactured circular ring to the front part 221 and the rear part 222.Further, the front part 221 may be formed to have a greater outerdiameter than that of the rear part 222.

As illustrated in FIGS. 4 and 5 , in the tensile force adjustmentcylinder 24 according to the embodiment of the present disclosure, thefront surface 24 a with which the rear surface 23 b of the elasticmember 23 is in close contact has a flat surface having uniform flatnesswithout a surface step, is in close contact with the rear surface 23 bof the elastic member 23 without a step, and thus guides the elasticmember 23 so that the elastic member 23 may be horizontally contractedand extended without being twisted.

As illustrated in FIG. 5 , the rear part 222 of the plunger shaft 22 isinserted into and coupled to the tensile force adjustment cylinder 24 toslidably move in a lengthwise direction of the tensile force adjustmentcylinder 24. In this way, as the rear part 222 is inserted into andcoupled to the tensile force adjustment cylinder 24, the plunger shaft22 may linearly and horizontally move through the tensile forceadjustment cylinder 24 without shaking.

For example, the tensile force adjustment cylinder 24 may have a ballbearing including an outer ring 241, an inner ring 242, and a ball 243installed between the outer ring 241 and the inner ring 242. In thiscase, a contact surface between the outer ring 241 and the inner ring242 in contact with the rear surface 23 b of the elastic member 23 isformed in a flat surface without a surface step to prevent the twistingof the elastic member 23 as described above.

Further, the outer ring 241 may be formed of stainless steel that isresistant to corrosion and oxidation, and the inner ring 242 may beformed of a synthetic resin material that is resistant to corrosion.Therefore, a supporting force can be provided, and smooth movement canbe provided when the plunger shaft 22 slidably moves.

Meanwhile, a ball bearing having a structure in which a part of a ballpasses through the inner ring and protrudes to the hollow of the tensileforce adjustment cylinder 24 may be used as the tensile force adjustmentcylinder 24. In this case, when slidably moving along the hollow of thetensile force adjustment cylinder 24, the plunger shaft 22 slidablyinserted into the hollow of the tensile force adjustment cylinder 24 isin direct contact with the ball passing through the inner ring andprotruding, and thus can move more smoothly due to a rolling movement ofthe ball.

As illustrated in FIG. 3 , the sleeve 21 according to the embodiment ofthe present disclosure, which is a screw-type sleeve having a threadformed on an outer surface thereof, includes a front part 211 and a rearpart 212 having different outer diameters.

As illustrated in FIG. 4 , threads are formed on outer surfaces of thefront part 211 and the rear part 212. Further, an alignment key groove212 a formed in a horizontal cut surface so that a tensile forceadjustment position of the archery cushion plunger 20 is easilyidentified may be formed on one side of the outer surface of the rearpart 212.

A thread to which a tensile force adjustment housing 25 is screw-coupledis formed in the outer surface of the rear part 212 of the sleeve 21.Further, when a tensile force is adjusted using a dial manner throughthe tensile force adjustment housing 25, tensile force adjustmentgrooves 212 b are formed on the rear part 212 at regular intervals sothat the tensile force adjustment grooves 212 b are perpendicular to arotational direction of the thread formed in the rear part 212 touniformly adjust a tensile force adjustment value.

A plurality of tensile force adjustment grooves 212 b are formed in arotational direction of the sleeve 21 at regular intervals. A tensileforce of the elastic member 23 may be determined based on a position ofthe tensile force adjustment groove 212 b to which a ball 26 a of a ballplunger 26 is coupled, and thus a strength of a pressure point of thearrow can be finely adjusted.

Meanwhile, the first tensile force adjustment groove among the tensileforce adjustment grooves 212 b may be formed in parallel to thealignment key groove 212 a of the sleeve 21 so that an archer may easilyrecognize the strength of the adjusted tensile force. Alternatively, azero point (scale) may be displayed to correspond to the firsts tensileforce adjustment groove. Based on this, the archer may easily recognizethe strength of the pressure point of the currently adjusted arrow tocorrespond to the tensile force adjustment groove located in a clockwisedirection or a counterclockwise direction.

As illustrated in FIGS. 3 and 4 , the tensile force adjustment housing25 has a hollow 25 a to which the sleeve 21 is coupled. Further, athread to be screw-coupled to the thread formed in the rear part 212 ofthe sleeve 21 is formed in an inner circumferential surface of thehollow 25 a. Thus, the tensile force adjustment housing 25 may linearlyreciprocate along the sleeve 21 in a rotational direction through screwcoupling with the sleeve 21. For example, when rotating in a tighteningdirection, the tensile force adjustment housing 25 moves leftward alongthe sleeve in FIG. 5 , and when rotating in an untightening direction,the tensile force adjustment housing 25 moves rightward in FIG. 5 .

As illustrated in FIG. 5 , a rear end of the tensile force adjustmenthousing 25 may be sealed. This is for preventing foreign substances frombeing introduced into the tensile force adjustment housing 25. Further,the tensile force adjustment cylinder 24 inserted into the hollow 25 aof the tensile force adjustment housing 25 has a rear surface 24 b thatis supported on an inner surface of the sealed rear end of the tensileforce adjustment housing 25 in a right direction in FIG. 5 . Thus, asthe tensile force adjustment housing 25 moves, the tensile forceadjustment cylinder 24 inserted and coupled thereinto also moveshorizontally in conjunction with the movement of the tensile forceadjustment housing 25.

As illustrated in FIG. 4 , a fastening hole 25 b into which the ballplunger 26 for fixing the tensile force adjustment housing 25 to thesleeve 21 is inserted and fastened is formed above the tensile forceadjustment housing 25.

The ball plunger 26 may be fixedly fastened to the fastening hole 25 bthrough a nut N and a washer W.

As illustrated in FIG. 5 , the fastening hole 25 b is formed tocommunicate with the hollow 25 a of the tensile force adjustment housing25. The ball plunger 26 coupled to the fastening hole 25 b has a ball 26a installed at a lower end thereof, and thus when the tensile force isadjusted, the ball 26 a may be more smoothly caught by the tensile forceadjustment groove 212 b.

Meanwhile, as illustrated in FIG. 3 , a fixing nut 27 for mounting thecushion plunger 20 to a bow may be installed in the sleeve 21. Forexample, the fixing nut 27 may be formed through an aluminum anodizingprocess. Further, as illustrated in FIGS. 4 and 5 , a thread is formedon an inner circumferential surface of the hollow 27 a to bescrew-coupled to the thread formed on an outer surface of the sleeve 21and moves leftward and rightward along the sleeve 21 in the rotationaldirection. Further, a fastening hole 27 b to which a locking screw (notillustrated) is fastened is formed on an upper side to be fixed to thesleeve 21 at a predetermined position.

When viewed from the tip portion 221 a of the plunger shaft 22, thetensile force adjustment housing 25 may have a polygonal shape (forexample, a triangular shape) so that a gripping sense of a finger isimproved and the finger does not slide when the tensile force isadjusted. The fixing nut 27 may also have a triangular structure inconsideration of a gripping sense or the like.

Hereinafter, operation characteristics of the archery cushion plunger 20according to the embodiment of the present disclosure will be described.

As illustrated in FIG. 5 , in order to adjust the strength of thepressure point of the arrow, when the tensile force adjustment housing25 rotates about the sleeve 21 in the tightening direction (clockwisedirection), the tensile force adjustment housing 25 moves in a leftwarddirection along the sleeve 21. The tensile force adjustment cylinder 24moves by being guided by the tensile force adjustment housing 25 inconjunction with the tensile force adjustment housing 25. As the tensileforce adjustment cylinder 24 moves, a rear part of the elastic member 23is pressed to increase the tensile force. The strength of the pressurepoint of the arrow increases to correspond to the increase in thetensile force of the elastic member 23.

In contrast, when the tensile force adjustment housing 25 rotates in theuntightening direction (counterclockwise direction), the tensile forceadjustment housing 25 moves in a rightward direction. Further, thetensile force adjustment cylinder 24 is pushed to the right side by anelastic restoring force of the elastic member 23 in conjunction with therightward movement of the tensile force adjustment housing 25.Accordingly, a pressing force applied to the elastic member 23 isreduced or eliminated, and thus the tensile force is reduced. Thestrength of the pressure point of the arrow is reduced to correspond tothe reduction in the tensile force of the elastic member 23.

As described above, according to an archery cushion plunger according tothe present disclosure, a structure is changed so that a plunger shaftin contact with an arrow shaft passes through a center of an elasticmember, the plunger shaft stably grips the center of the elastic member,and thus deformation of the elastic member can be fundamentallyprevented even when a pressure is applied to front and rear sides of theelastic member during adjustment of a tensile force.

Further, according to the archery cushion plunger according to thepresent disclosure, a front surface and a rear surface of the elasticmember installed between the plunger shaft and a tensile forceadjustment cylinder are precisely polished so that the front surface andthe rear surface are in close contact with a contact surface between theplunger shaft and the tensile force adjustment cylinder without asurface step. Therefore, a pressing force applied from the tensile forceadjustment cylinder to the elastic member and from the elastic member tothe plunger shaft is horizontally and stably transmitted, a tip portionof the plunger shaft is always in horizontal contact with the arrowshaft, and thus horizontal vibration can be stably compensated for.

Thus, according to the archery cushion plunger according to the presentdisclosure, the tip portion of the plunger in contact with the arrowshaft is always in horizontal contact with the arrow shaft to stablycompensate for horizontal vibration, stable flight of an arrow isinduced, and thus a hit rate of the arrow can be improved.

Further, according to the archery cushion plunger according to thepresent disclosure, the tensile force adjustment cylinder into which arear part of the plunger shaft passing through the elastic member isinserted and coupled and which interlocks with a tension adjustmenthousing that rotates in a dial manner to adjust a tensile force of theplunger shaft is formed in a ball bearing structure, and thus, when thetensile force is adjusted, the plunger shaft can move more smoothly thanwhen the plunger shaft moves horizontally and linearly in a slidingmanner inside the tensile force adjustment cylinder.

Further, according to the archery cushion plunger according to thepresent disclosure, tensile force adjustment grooves are formed in anouter surface of a sleeve at regular intervals, an adjusted tensileforce is fixedly locked using a ball plunger coupled to the tensileforce adjustment housing after the tensile force is adjusted by rotatingthe tensile force adjustment housing in a dial manner, and thus atensile force adjustment operation can be more smoothly performed.

As above, embodiments of the present disclosure have been described andillustrated using specific terms, but these terms are only intended toclearly describe the present disclosure. Further, it is obvious that theembodiments and the described terms of the present disclosure may bevariously changed and modified without departing from technical spiritand scope of the appended claims. The modified embodiments should not beindividually understood from the spirit and scope of the presentdisclosure and should belong to the appended claims of the presentdisclosure.

What is claimed is:
 1. An archery cushion plunger comprising: a sleeve;a plunger shaft that buffers a lateral pressure of an arrow shaftthrough a tip portion exposed to one end of the sleeve; an elasticmember which is embedded in the sleeve and has a front surfacehorizontally stopped and supported on the plunger shaft in a directionof the arrow shaft and through which the plunger shaft is coupled at acenter thereof; a tensile force adjustment cylinder into which a rearpart of the plunger shaft is slidably inserted and of which a frontsurface is in contact with a rear surface of the elastic member suchthat the tensile force adjustment cylinder is horizontally stopped andsupported; and a tensile force adjustment housing that is screw-coupledto an outer surface of the sleeve to rotate about the sleeve and adjustsa tensile force of the elastic member by linearly moving the tensileforce adjustment cylinder along the plunger shaft while linearly movingalong the sleeve in a rotational direction.
 2. The archery cushionplunger of claim 1, further comprising a ball plunger that moves into ahollow of the tensile force adjustment housing through a fastening holeformed in the tensile force adjustment housing and is vertically coupledto a tensile force adjustment groove formed in a rear part of the sleeveinserted into the tensile force adjustment housing.
 3. The archerycushion plunger of claim 2, wherein an alignment key groove is formed inthe outer surface of the sleeve in a horizontal cut surface structure sothat the alignment key groove is horizontally parallel to a firsttensile force adjustment groove among the tensile force adjustmentgrooves formed in the sleeve.
 4. The archery cushion plunger of claim 1,wherein the tensile force adjustment cylinder includes: an outer ring;an inner ring inserted into the outer ring; and a ball installed betweenthe outer ring and the inner ring.
 5. The archery cushion plunger ofclaim 1, wherein the plunger shaft includes: a front part having the tipportion; a rear part connected to a rear end of the front part andinserted into the tensile force adjustment cylinder; and a step partthat is formed at a boundary between the front part and the rear part,protrudes outer surfaces of the front part and the rear part, and is incontact with the front surface of the elastic member to be stopped andsupported.
 6. The archery cushion plunger of claim 1, wherein aseparation prevention step by which a step part of the plunger shaftsupported by the front surface of the elastic member in the direction ofthe arrow shaft is stopped is formed inside the sleeve.
 7. The archerycushion plunger of claim 1, further comprising a fixing nutscrew-coupled to the outer surface of the sleeve.
 8. The archery cushionplunger of claim 1, wherein when viewed in the direction of the arrowshaft, the tensile force adjustment housing is formed in a polygonalstructure.
 9. The archery cushion plunger of claim 1, wherein the frontsurface of the rear force of the elastic member are polished to have asurface step of 0.3 mm or less.